diff --git a/CHANGELOG.md b/CHANGELOG.md
index b314b98..56cbe1e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+# 2.2.0 
+
+- `Promise.promisify` now uses `coroutine.wrap` instead of `Promise.spawn`
+
 # 2.1.0
 
 - Add `finallyCall`, `andThenCall`
diff --git a/lib/README.md b/lib/README.md
index 4adf8c1..1cc638b 100644
--- a/lib/README.md
+++ b/lib/README.md
@@ -146,9 +146,6 @@ docs:
           type:
             kind: function
             params: "...: ...any?"
-        - name: selfValue
-          type: any?
-          desc: This value will be prepended to the arguments list given to the curried function. This can be used to lock a method to a single instance. Otherwise, you can pass the self value before the argument list.
       returns:
         - desc: The function acts like the passed function but now returns a Promise of its return values.
           type:
diff --git a/lib/init.lua b/lib/init.lua
index 825ee3a..a8ca86e 100644
--- a/lib/init.lua
+++ b/lib/init.lua
@@ -335,15 +335,11 @@ end
 --[[
 	Converts a yielding function into a Promise-returning one.
 ]]
-function Promise.promisify(callback, selfValue)
+function Promise.promisify(callback)
 	return function(...)
 		local length, values = pack(...)
 		return Promise.new(function(resolve)
-			if selfValue == nil then
-				resolve(callback(unpack(values, 1, length)))
-			else
-				resolve(callback(selfValue, unpack(values, 1, length)))
-			end
+			resolve(coroutine.wrap(callback)(unpack(values, 1, length)))
 		end)
 	end
 end